Composite module - Natal Chart, Sidereal Zodiac and South Node
In this article I would like to answer to some question that I receive from time to time. This is a question why we do not use in Composite module ("Astronomy" button) some Natal chart and Sidereal Zodiac and we are not recommended to use South Node point.
The idea of Composite module is that here we analyze each degree of Zodiac, thus we do not need to know the Natal Chart as such. The degrees where some natal planets are positioned will be taken into account in any case. The good thing here is that we can eliminate the long discussion about "true" natal charts.
In order to explain the issue with the Nodes, I put here three composite cycles:
red - North Node cycle
blue - South Node cycle
green - the cycle of the angle between North Node and Natal Sun:
These three curves are not close, they are absolutely identical.
Why? I will try to explain this effect from the point of view of the information theory.
Does the position of South Node provide us some new information in comparison to North Node position?
The answer is: No. It is so because the South Node is the point exactly opposite to North Node. It means that if some composite cycle shows the TOP around zero of Capricorn of North Node position, that same TOP occurs around zero of Cancer of South Node position:
The composite module analyses each degree of Zodiac, so if we shift the initial point on 180 degrees ,nothing happens. In other words we can take a composite diagram for North Node and rename marks there: Aries to Libra (opposite sign), Taurus to Scorpio, Gemini to Sagittarius, etc., and this new diagram will represent the composite for South Node.
Exactly the same logic is applied to composite of North Node-Natal Sun (or any other planet). We simply shift the initial points, it will shift the palette of sensitivity to some angle, but the final projection line will be exactly the same.
So remember this formula:
N. Node cycle = S. Node Cycle = N. Node - Natal (any) planet cycle
Now I would like to put some words about Sidereal Zodiac. The difference between tropical and Sidereal Zodiac (ayanamsa) changes very slowly, approximately 1 degree in 70 years. It means that the composite cycle calculated for any planet in tropical Zodiac will be very close to the composite for this planet in Sidereal Zodiac.
As an example I have calculated two Annual (Sun) cycles for tropical (red) and Sidereal Zodiacs (blue):
As you see they are very very close. I used DOW from 1885 year, so the ayanamsa has changed practically on 2 degrees within this period.
This why in Timing Solution we do not use Natal, Sidereal Zodiac and South Node points. We simply exclude double objects; using them for calculation of the projection line causes bad side effects.